Could we now do, what it is so easy to do with the egg of a fowl,--carefully take off a little portion of this outer shell, we should be able to inspect its contents more accurately. But in the case of most who read this book, this extremely delicate task will prove after many trials probably a hopeless failure. Let us state, therefore, what some expert and talented observers have found within the insect's egg. It appears, then, that although there is both a "yolk" and a "white" in the tiny egg before us, that they are not quite so distinct as in the bird. Yet, they are sufficiently separate from one another to make their differences complete. Probably the reader has noticed in the hen's egg a little round spot in the middle of the "yolk" or yellow portion; from this the future bird is produced. Although from their extreme minuteness it is difficult to detect anything of this kind in the eggs of insects, some observers state they have seen a similar little spot in them also. Thus, M. Herold says, that in the eggs of the very insect whose nest we have robbed, the garden spider, "this little spot can be seen as a minute white point immediately under the shell, and in the middle of its circumference." This was seen by holding it up to the light, and the spot was more carefully examined by gently pressing the contents of a spider's egg upon a watch-glass. Mr. Rennie says, that "the point where the caterpillar originates, answering to the scar in the eggs of birds, we can readily distinguish even by the naked eye in the larger species of eggs, as it lies always immediately under the shell." But it may be doubted whether, without the assistance of some one versed in entomology, many who make the same attempt, will succeed. So much depends in looking at any object upon whether we know what to look for or not, so that things which are as clearly seen as possible by the eyes of the initiated, are not seen at all by any others. To perceive some things in natural history, and many in science, the senses of sight, hearing, and touch, require to be well educated, and they then become apparent enough.
And is this all that we can mention about the structure of an egg? This indeed is all. Can it be possible? Is there no striking and broad difference to mark the nature of the future insect? Is the egg of a spider the same in the number and nature of its parts as that of a butterfly, or the egg of a gnat as that of a beetle? Surely, as we should imagine, there must be some important differences between these, otherwise why such immense differences in the perfect insect? Could any one imagine that a grasshopper and a house-fly, so strangely unlike each other in their perfect forms, originated in eggs to either of which the same description of an insect's egg would accurately answer, and leave nothing out? However great our amazement, the fact is unquestionable. The egg of every insect at first consists of an outer covering, a white, a yolk, and the little spot we have alluded to. We might have thought that in creating so many different species of insects, which differ so surprisingly in form as the insect tribes do, the great Creator would have formed their eggs essentially different too. But, except in the matter of shape, all are originally alike; and the wisest philosopher is unable to inform us of any essential difference in the eggs of insects at first. The eye of God, who knows the end from the beginning, sees some difference inappreciable to the eye of man. He said to this kind, "Be thou thus," and to that, "Be thou different;" but until the time comes when the young insect is much more advanced, it is not possible for us to recognise those marks of variety which His hand has laid upon them from the beginning.